AR sales invoice problem

["Jussi Kirjavainen" <..hidden..>]

Hi, I guess it's bad form to post multiple times, but..

I'm having problems with AR sales invoice. I can't get any account to
show in Record in -dropdown menu. I have tried all kinds of
combinations, even totally senseless ones, but nothing shows up. 

In AR transactions I can get my sales account to show as it should in
Account, before Description field. Account is set up as type Income,
with Income in "include in dropdown menus" Receivables selected. But it
doesn't work with sales invoice for some reason.

Am I missing something obvious? Is this explained somewhere in
manual? I'd like to start using the AR module, so far I've managed with
GL only... BTW I'm still using v.1.2.7

Thanks for help!