Just saw this article relating to use of open source on WP7.
I am not a lawyer so it is hard to say whether this impacts CSLA or not.
I suspect not, since CSLA isn't necessarily open-source in a pure sense. It is owned by Marimer LLC, and made available for use under a liberal license. This license allows the use of the framework to build software for which you charge money for purchase, distribution, etc.
The most likely reason for Microsoft's license restriction isn't the conspiracy theory in that article, but rather that Microsoft takes money for distributing software through the Zune store. If part or all of the license for someone's software prevents legal distribution of software in exchange for money, then Microsoft would be legally liable.
It would then get very murky to say "well, the customer only paid for the non-LGP parts of the download, not the LGPL parts". How would that work when the customer paid $2.99 and downloaded one set of code that includes both legal and (now) illegal bits.
If Microsoft were to deny the use of CSLA on the phone I'd have to change my license. But I doubt that will be necessary since the CSLA license doens't preclude the use of the framework in commercial apps or the distribution of commercial apps.
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