Well, here are a couple of things I've done that have made a difference where I work. Mind you, they only work if the person shows interest.... ie. they continuously ask you questions about perl.
This only works on about 1 in 10 people, because most aren't really interested in spending their time learning something new.
- Give them a book.... I just gave my 2nd ed. Camel Book to someone who has continuously showed interest. He's just started learning perl. I loaned a camel book to another programmer who learned a moderate level of perl in 2 months. (he familiarized himself with CPAN quickly) If they don't use it, you can always ask for the book back.
- Teach them during work anytime you have a few minutes. I've been asked to do a few 10 line projects for work in the past. When I get them, I scratch out the code on a dry erase board and let someone else punch it in and run it. Even though they didn't come up with the code themselves they got some enjoyment out of making it happen. They generally would come back later and ask questions about how the code works.
and remember, you can only teach someone if they want to learn