How do I call email program on client machine using custom code?

We have a requirement to call email program on client machine at a specific event using Oracle Forms in R12. Requirement was being fulfilled previously using OLE2 call in reports 6i trigger. Now the same requirement has arisen for R12. We have created a test form and configured webutil on application server using the guidelines. Webutil has successfully been integrated and libraries/jar files (frmwebutil.jar,jacob.jar) are being loaded into the application forms. But when we call the CLIENT_OLE2 code, it raises error ORA-06508.

Please guide to achieve the requirement in R12.

Regards,

Danny