facebook share widget issue with dynamic pages
Those codes (%3A, %2F) are generated by the urlencode() function, so I believe you should just be able to call the thisPageUrl() function by itself to get the URL you want:
<?php echo thisPageUrl(); ?>
It is good practice to use urlencode() on any dynamic text you want to include in a URL, however, with how the Facebook script is using the value, it isn't necessary in this case.
Let me know if that does the trick!