The trouble with PerlScript is that browser support is limited. Very limited. In fact, looking on the ActiveState site it seems that the plugin (which was IE only) isn't available any more.
The latest version of ActiveState Perl (ActivePerl 5.6.1.638) still contains PerlScript. I use this version and have no problem to run PerlScript in IE.
CountZero
"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law