diff --git a/library/PhpLatex/Parser.php b/library/PhpLatex/Parser.php
index db033f2..e487c27 100644
--- a/library/PhpLatex/Parser.php
+++ b/library/PhpLatex/Parser.php
@@ -318,6 +318,7 @@ protected function _createEnviron($name, $mode, $environ = null) // {{{
         assert(($mode & ($mode - 1)) === 0); // mode must be a power of 2
 
         $math = false;
+        $optArgs = array();
         $args = array();
 
         if (isset($this->_environs[$name])) {
@@ -342,12 +343,23 @@ protected function _createEnviron($name, $mode, $environ = null) // {{{
             // or displaymath), if so, prepare math node instead of environ node
             $math = isset($spec['math']) && $spec['math'];
 
+            $parseArgs = isset($spec['parseArgs']) ? $spec['parseArgs'] : true;
+
+            $numOptArgs = isset($spec['numOptArgs']) ? intval($spec['numOptArgs']) : 0;
+            while (count($optArgs) < $numOptArgs) {
+                if (false !== ($arg = $this->_parseOptArg($mode, $environ, $parseArgs))) {
+                    $optArgs[] = $arg;
+                } else {
+                    break;
+                }
+            }
+
             // parse args, will be placed as environs first children, with
             // no spaces between them, btw: \begin{tabular}c is a perfectly
             // correct specification for a single-column table.
             $nargs = isset($spec['numArgs']) ? intval($spec['numArgs']) : 0;
             while (count($args) < $nargs) {
-                if (false === ($arg = $this->_parseArg($mode, $environ))) {
+                if (false === ($arg = $this->_parseArg($mode, $environ, $parseArgs))) {
                     $arg = $this->_createNode(self::TYPE_GROUP, $mode);
                 }
                 $arg->setProp('arg', true);
@@ -364,6 +376,10 @@ protected function _createEnviron($name, $mode, $environ = null) // {{{
             $node->math = $math;
         }
 
+        foreach ($optArgs as $arg) {
+            $node->appendChild($arg);
+        }
+
         foreach ($args as $arg) {
             $node->appendChild($arg);
         }
diff --git a/library/PhpLatex/Renderer/Abstract.php b/library/PhpLatex/Renderer/Abstract.php
index dc5aac9..60402fb 100644
--- a/library/PhpLatex/Renderer/Abstract.php
+++ b/library/PhpLatex/Renderer/Abstract.php
@@ -71,7 +71,7 @@ public static function toLatex($node) // {{{
                     $argsEnd = 0;
 
                     foreach ($children as $child) {
-                        if ($child->arg) {
+                        if ($child->arg || $child->optional) {
                             ++$argsEnd;
                         } else {
                             break;
diff --git a/library/PhpLatex/environs.php b/library/PhpLatex/environs.php
index 3e75b95..ab0c035 100644
--- a/library/PhpLatex/environs.php
+++ b/library/PhpLatex/environs.php
@@ -2,62 +2,65 @@
 
 return array(
     'verbatim'    => array(
-        'verbatim'  => true,
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate'),
-        'starred'   => true,
+        'verbatim'   => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate'),
+        'starred'    => true,
         // verbatim in tabular causes
         // ! LaTeX Error: Something's wrong--perhaps a missing \item.
     ),
     'Verbatim'    => array(
-        'verbatim'  => true,
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate'),
+        'verbatim'   => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate'),
     ),
     'lstlisting'  => array(
-        'verbatim'  => true,
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate'),
+        'numOptArgs' => 1,
+        'verbatim'   => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate'),
     ),
     'enumerate'   => array(
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate'),
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate'),
     ),
     'itemize'     => array(
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate'),
+        'numOptArgs' => 1,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate'),
         // itemize in tabular causes
         // ! LaTeX Error: Something's wrong--perhaps a missing \item.
     ),
     'displaymath' => array(
-        'math'      => true,
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate'),
+        'math'       => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate'),
         // displaymath in tabular causes
         // ! LaTeX Error: Bad math environment delimiter.
     ),
     'math'        => array(
-        'math'      => true,
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate', 'tabular'),
+        'math'       => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate', 'tabular'),
     ),
     'equation' => array(
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'math'      => true,
-        'starred'   => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'math'       => true,
+        'starred'    => true,
     ),
     'eqnarray' => array(
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'math'      => true,
-        'starred'   => true,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'math'       => true,
+        'starred'    => true,
     ),
     'tabular' => array(
-        'numArgs'   => 1,
-        'mode'      => PhpLatex_Parser::MODE_TEXT,
-        'environs'  => array('itemize', 'enumerate', 'tabular'),
+        'numArgs'    => 1,
+        'numOptArgs' => 1,
+        'mode'       => PhpLatex_Parser::MODE_TEXT,
+        'environs'   => array('itemize', 'enumerate', 'tabular'),
     ),
     'array' => array(
-        'numArgs'   => 1,
-        'mode'      => PhpLatex_Parser::MODE_MATH,
+        'numArgs'    => 1,
+        'mode'       => PhpLatex_Parser::MODE_MATH,
     ),
 );
diff --git a/tests/PhpLatex/Test/ParserTest.php b/tests/PhpLatex/Test/ParserTest.php
index 08fc6bf..258ba3c 100644
--- a/tests/PhpLatex/Test/ParserTest.php
+++ b/tests/PhpLatex/Test/ParserTest.php
@@ -128,4 +128,10 @@ public function testNewlinesAfterComment()
         $tree = $this->parser->parse("A% comment\n\nB");
         $this->assertSame("A\par B", PhpLatex_Renderer_Abstract::toLatex($tree));
     }
+
+    public function testEnvironmentWithArgsConfig()
+    {
+        $tree = $this->parser->parse("\\begin{tabular}[t]{|c|c|c|}\ncell1 & cell2 & cell3\n\\end{tabular}");
+        $this->assertSame("\\begin{tabular}[{t}]{|c|c|c|}\n cell1 & cell2 & cell3\n\\end{tabular}", PhpLatex_Renderer_Abstract::toLatex($tree));
+    }
 }