SharePoint User Group UK

I'm about ready to rip my hair out on this.  I've called MS and they have been useless, hopefully I can get my money back...

Environment:
Single Sharepoint box (2007 Enterprise with SP1)
SQL 2000 SP4 on a different server
Exchange 2007 SP1

I am trying to follow the MS practices of using separate domain accounts for each portion of sharepoint, and I think this might be the problem.

FWIW, I did get everything working successfully one time in a test environment, but I Was using a single service account rather than multiple ones.

When I try to e-mail enable a library I get the generic "error in application."  I've double-checked my OU path, it is correct.  I've given *every* service account full control over that OU.

Here are the accounts I have:
svcMOSS_DB - main farm account, I guess this is used as the Central Admin app pool as well? - the Timer service is running as this account too.  This is also running the app pool for the SSP.
svcMOSS_SSP1 - Shared Svc. Provider account
svcMOSS_ap1 & _ap2 - app pool accounts

Question -- will it not be able to create a contact in AD unless I setup the SMTP send connector first?  I've been skipping that step so far since the contact isn't even creating in AD, I figured I can get the mail flowing after I make sure the contacts create.

I'm totally stumped.  I'd love any help I can get here.  I have followed the whitepaper in the past and I got it working in my test environment ages ago, but as I said I was using a single service account (that also happened to have domain admin rights).  Now that I'm trying to do least privledges it's all falling apart... :(

I am quite new to all this, but I think a lot of the time people foget to ensure the app pool account has write permissioins to the app database as well as the OU.