libmono-cil-dev 2.6.7-5ubuntu3 (i386 binary) in ubuntu natty

 This package contains development headers for the Mono Base Class Libraries.
 .
 Mono is a platform for running and developing applications based on the
 ECMA/ISO Standards. Mono is an open source effort led by Novell.
 Mono provides a complete CLR (Common Language Runtime) including compiler and
 runtime, which can produce and execute CIL (Common Intermediate Language)
 bytecode (aka assemblies), and a class library.