simple tags: can somebody translate this error message for me?

I had Simple Tags up and working, but someplace along the way I must have made a change without realizing it. I’ve since disabled Simple Tags, but when it is enabled, every post shows this error:

Warning: preg_replace() [function.preg-replace]: Unknown modifier ‘d’ in /home/rosina/public_html/rosinalippi-com/weblog/wp-content/plugins/simple-tags/simple-tags.php on line 222

Would it be a disaster if I went into the plugin code and deleted that unknown modifier ‘d’ from line 22? Or can anyone tell ms what I should do instead?

Thank you for any help provided.