in syntaxPost function,
1. Add global variable just below $IsCodeInPost variable, define as array of codetype, and initilize to zero (0). like below:

global $CodeType;

$CodeType = array (“cpp”=> 0, “csharp”=>0, “css” => 0, “delphi” => 0,”java”=>0, “jscript” => 0, “php”=> 0, “python”=>0, “ruby” => 0, “sql” => 0, “vb”=> 0, “xml” => 0);

2. In loop to search/replace [source] add the following code to set the CodeType match to 1

foreach( $theSources[2] as $sourceID => $sourceBlock ) {
$theBrush= ……
.
$CodeType[$theBrush] = 1;
}

in syntaxFooter: check if $CodeType["vb"] if its value is 1 then include shBrushVb.js and none otherwise.

ok, hope this help.
i have practiced it in my pemikiran.com, i will send the modified code if you like.