Hi Dietmar,
I'd recomend to get the latest version of sendmail. With that you get even 'smtp auth' for your roaming users. The spam and relaying filters are just good and with the help you find on www.sendmail.org you secure the system within litle time.
Yeah, I've already get Sendmail 8.10.2 wich include support for SMTP_AUTH, but it requires third part patches. I tried to build a RPM package applying these patches while keeping the original patches that apply to SuSE 6.4 sendmail.spm, but wasn't successful. It seems that I'll take me more time to adjust the patches and the sendmail.spec file and put it to work (building the RPM package) than I have. Yeah, I know that I can just "tar zxvf sendmail.version.tar.gz" and then "./build [option]", however I like to keep everything in the rpm database. Moreover I take care of various servers and RPM helps me keeping everything in order on all machines with much less effort. Thanks, Bráulio Weimann Gergull