C/C++ function/class library for MIME

I need a C++ class library (alternatively - C function) that do some kind of MIME coding. What exactly I need is to have class/function that can take a file from some directory and create an e-mail message with this file in attachment and send it by SMTP. It should also can take e-mail address and possibly some other information (for instance the address of e-mail server and some other parameters) Sending email messages should be done in two ways: using local mail server (that should forward the message to the recipient) and sending the message directly to the recipients mail server. Source code should be platform independent. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform platform independent but probably Windows