Stream Out Errors - Stack Used By PCell Evaluation Internal Overflows

  I am running Virtuoso version IC6.1.3.500.10 and I have been having some problems streaming out a P-Cell to GDS.  I have a custom SKILL P-Cell code that loads properly in Cadence and does not have any P-Cell evaluation errors.  I have four tiles that uses this P-Cell that are placed in a holding cell and I get the following error when I stream out:

*WARNING* ("dbCreateParamInst" 0 t nil ("*Error* dbCreateParamInst: The stack used by pcell evaluation internal overflows.\n"))
ERROR (211): Pcell evaluation has failed. This is because of either a syntax error or the usage of an unsupported XStream function in Pcell SKILL code. For more information refer to the standard output or CDS.log. To continue, either specify the ignorePcellEvalFail option in Stream In/Out options or correct the Pcell SKILL code.
 XStream failed

  The strange thing is that each of the four tiles individually streamed out successfully to GDS.  Can somebody help give a better description of the error: "The stack used by pcell evaluation internal overflows"?  Does anybody have any idea of how this can be prevented?

 Thanks in advance, Paul