dear friend
i created database using oracle relational access administartor as per the docs supplied with oracel express server ..Now when i try to bulid project using express object it ask me for
login to relational source with username guest ...If i supply any username that is in oracle rdbms from which i develop database like sampleolap or system username it give me error like database pointer is null
error:no_guest:guest login not allowed from client startup

if i click detail tab it show
Error #132 in XPDBOBJS.DLL: Non-fatal (0300): The database pointer is NULL.
Error #12150 in XPCUBE: Non-fatal (0300): Data Manager is unable to generate transmission.
Error #10300 in XDMRESP: Non-fatal (0300): ERROR: NO_GUEST: Guest login not allowed from client startup

can any one help me