[Dovecot] FC2 POP3/SMTP Configuration

[Linux Stuff]

OK, let me try this again. . . .

I'm a newbie to dovecot and a little bit less of a newbie to linux.  I 
am in the process of moving my server from RH9 to FC2.  The only 
obstacle remaining is my email.  I run dovecot (v0.99.14) POP3 and 
sendmail (8.12.11-4.6) with Mozilla (1.4.2 and others), Thunderbird 
(1.0.2) and Netscape (7.1 on PC's, etc) mail clients - mostly PC's (W2K, 
WXP).  They all can read their mail but none of the users can send any 
mail.  I have also tested with Outlook and it works!?  Ximian Evolution 
(1.4.6) also works!???   Depending on the state of the dovecot.conf 
file, I get the following:

Mar 28 16:04:14 corvette sendmail[5810]: unable to open Berkeley db 
/etc/sasldb2: Invalid argument
Mar 28 16:04:14 corvette sendmail[5810]: unable to open Berkeley db 
/etc/sasldb2: Invalid argument
Mar 28 16:04:14 corvette sendmail[5810]: no secret in database

Why do Outlook and Ximian work and the others do not?
I know I must be missing something in my config file.
Ideas??

Thanks