There is no Palm Perl. Nor is there likely to be a full perl port (a limited subset would perhaps be workable), at least for Palm OS 4 and below, because (approximately) it would first involve writing a Unix-ish environment on the Palm. From a Unix point of view, the Win32 and VMS environments look familiar compared to Palm OS.

I've not looked at Palm OS 5 and higher, but my understanding is that OS 5 is very similar to OS 4 architecturally.

There *are* a few languages you can put on your Palm if you need to write code on there. I like Quartus Forth, and Lispme. There is also a limited Python port, as well as various BASICs and Small C.