[Zope] get OUT args from ZOracleDA

Hi, I have Zope 2.1.5 and Oracle 8.0.5 running on the same Linux box. ZOracleDA was installed successfully and bridged Zope and Oracle. I can call my stored procedure by creating Z SQL Method like: begin procName(arg1, arg2,...); end; But I cannot get return arguments (OUT args) no matter how the Z SQL Method is set. I have tried the interfaces mentioned in DCOracle documents, but failed. The only work-around I've found is creating extenal methods and import DCOracle via python. Is there any way to get the OUT arguments from Z SQL Method? Thanks a lot! Chien-pin