how to add reference at run time in C# project

hi all,

how can i add an assembly(dll) as reference in a C# project at run time.?! i need to add a reference at run time.!? i.e normally we add references by Right-Clicking References in Solution Explorer and we can browse for any dll and add it in references. i need to do this using code.

like if i ave a class library(dll) in "C:\Documents and Settings\Pragadheesh\My Documents\Visual Studio 2005\Projects\qwerty\qwerty\bin\Debug\qwerty.dll"

i need to add this dll as reference to my project. how can i do this at run time.?

thanks in advance.