The following error occurs when clicking to change signature

PHP Code:
Call to undefined method vB_BbCodeParser::vB_BbCodeParser() on line 69 in /home/wowzygor/public_html/forum/includes/class_sigparser.php
#0 /home/wowzygor/public_html/forum/profile.php(2786): vB_SignatureParser->vB_SignatureParser(Object(vB_Registry), Array, Array, '33726')
#1 {main}