Well, it's the same as the iPhone as far as order of connections, but there may be differences in length. (There are reports that iPhone earphones need a spacer to hold them ~1-2mm out.)

Anyway, I'm sure you could search the internet for pinouts of "Palm Treo™ smartphone" and "Apple iPhone (including 3G) and Blackberry Curve", or even look up Nokia's E62 and N91 to see which is the same.