Null pointer exception during calling RFC

Hi,

I am getting below error when i am calling RFC in webdynpro

The initial exception that caused the request to fail, was:

java.lang.NullPointerException

at com.sap.tc.webdynpro.modelimpl.dynamicrfc.AiiModelClass.createNewBaseTypeDescriptor(AiiModelClass.java:220)

at com.sap.tc.webdynpro.modelimpl.dynamicrfc.AiiModelClass.descriptor(AiiModelClass.java:186)

at com.bajaj.ess.test.Zrfc_Sopbdc1_Input.<init>(Zrfc_Sopbdc1_Input.java:51)

at com.bajaj.ess.TestCust.wdDoInit(TestCust.java:99)

at com.bajaj.ess.wdp.InternalTestCust.wdDoInit(InternalTestCust.java:154)

... 43 more

Thanks & Regards

muna