Thanks David.
I did the migration to .net deployed the dll,
But since it needed to be called by third party as a COM component ,
i wrapped it by com callable wrapper, as mentioned by bruce in below link,
SAP Sybase Forums - PowerBuilder - PB Futures Discussion - COM/COM+ Components
1. Decompile the assembly using ildasm.
2. Open the generated il file and find the following:
.custom instance void
[mscorlib]System.Runtime.InteropServices.ComVisibleAttribute::.ctor(bool) =
( 01 00 00 00 00 )
3. Change it to read:
.custom instance void
[mscorlib]System.Runtime.InteropServices.ComVisibleAttribute::.ctor(bool) =
( 01 00 01 00 00 )
4. Recompile the assembly using ilasm.
5. Run regasm on the new assembly to generate the registry entries.
This worked for me. 