spell check woes

i've been flitting around different email programs. outlook is too slow. my outlook express went kludgy on me. eudora was cumbersome. i'm using thunderbird right now, and i'm pretty fond of it. i had an adaptation problem though: the keyboard shortcuts for the spell checker are different than the ones i'm used to. consequently, i've used Alt-A thinking it would _A_dd the word in question. Alt-A in thunderbird is Replace All. so "Claire" went out as "Ilaire", and "i'm" as "h'm". Alt-A is hardwired into my brain and it's a key combination that one can execute without much hand movement, so i still don't intercept the erroneous command consistently.