John Zimmerman,
You are right. Every-time I try to check out data through ArcPad Data Manager, ArcMap 10 crashes and I am unable to check out my data.
I just called ESRI tech support and they said they would call me back some time today. If I get an answer I will post it on here.
Just for reference purposes. I'm running.
ArcMap10
Checking out data from SDE Geodatabase (Versioned)
HP Desktop PC
Windows XP Professional
Service Pack 3
3.5 GB of RAM
Quad-Core Processor
Juno SC
Windows Mobile 6.1 Classic
ArcPad 10