The default limit is around 250. There is a registry setting that can be used to get around that, but it will have to be set on any workstation/server where the report is run.
For Crystal 2008, the key is:
HKEY_LOCAL_MACHINE\SOFTWARE\Business Objects\Suite 12.0\Crystal Reports\DatabaseOptions\LOV\MaxRowsetRecords
Per recommendation from SAP, set the value to 15,000.
-Dell