Cannot even come up with the beginning of a regex

Hi all, it's been a while since I've written with a regex problem. This time, I'm stumped. I've got some text that needs to have five letters, if found not at the end of a word, to be replaced with different letters. For instance, should the letter "a" be found at the end of a word, leave it alone. Should the letter "a" be found anywhere else in the word (beginning, middle, or by itself) then change it into "A". Sound frustrating? It is, at least to me. Can someone help out? For those who want more details for curiosity's sake, I'm writing a Hebrew transliteration engine for the gibberish.co.il website. This function will handle the Final Letter situations. Thanks in advance. Dotan Cohen http://what-is-what.com http://gibberish.co.il א-ב-ג-ד-ה-ו-ז-ח-ט-י-ך-כ-ל-ם-מ-ן-נ-ס-ע-ף-פ-ץ-צ-ק-ר-ש-ת A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing?