Interoperating from VC++ 6.0 to Vcsharp1.1

guys help me out on this issue

i have a project with me which was developed using VC++6.0 (i have not worked in vc++),rather than , i dont know anything about what type of project is it. but when look at the readme.txt file i have found the string in the top of the file "MICROSOFT FOUNDATION CLASS LIBRARY" . I am seeing the below text also.

"AppWizard has created this application for you. This application not only demonstrates the basics of using the Microsoft Foundation classes but is also a starting point for writing your application."

From here you may understand that what type of project is this that is what i have written these text here.

Now i want to use one of the functions (for example myfunction())from VC++ 6.0 project in my window application which is developed using C#(framework 1.1).

One more thing , in my system i dont have visual studio 6.0 installled , rather , visual studio 2003.
i opened the unmanged project(vc++) in visual studio 2003 and tried to create .dll out of unmanged code(vc++) after changing the configuration setting. dll got created but i am not able create RCW( runtime callable wrapper) using tlbimp command line tool. i am getting error like " this is not correct com dll or assembly dll"

plz advice me what has to be done if you have solution for his.

thanks in advance.
jebasingh luccas