option #4: if the machine that they are running the code on happens to have a perl interpreter, just not exposed through their interface, write a wrapper script in the language of your choice that they do make available, which pipes the text of you perl source to the perl executable (either through pipe or system or what have you)... it's worth a try, anyway. (if they show you the output of a normal submission, even if it doesn't fulfill their requirements, submit a program that just searches the PATH and standard /usr/bin/perl and similar locations to see if perl exists and is executable).