derailleur

I was wondering: I have problems with my front derailleur jamming up when if gets muddy. Can I assume that higher end derailleurs will have less problems with muddy conditions? My current derailleurs are cheap ones, and I'm thinking of upgrading. Perhaps those members in muddy areas can help me out?

I find that I cannot go uphill alot because I cannot get it into the granny gear, and it's pretty frustrating.