Help with query-replace-regular expression

[jade_lindquist@hotmail.com]

I'm struggling with emacs' implementation of regexp. I'd certainly
appreciate some pointers.

I'd like to replace lines like: /*#midp1_0#*///<editor-fold>

with:

//#if midp1_0

the phrase midp1_0 could be debug or some other alpha plus _ sequence

Thus I've tried M-x query-tags-regexp:
from:  \\/\\*\\#\\([a-zA-Z_]+\\).*
to: //#if \\1

but I don't get any matches.

Pehaps I need to escape other characters?

Thanks,
jdl