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<p class=MsoNormal>As everyone&#8217;s probably aware Beta 3 was the first
release to officially start requiring .NET 3.5 to compile IronPython and the
DLR sources.&nbsp; I just wanted to let everyone know that we&#8217;ve also now
formalized what the minimum runtime requirements for IronPython 2.0 will
be.&nbsp; The short of this is that IronPython (and the DLR) will start
requiring <b>.NET 2.0 SP1</b>.&nbsp; The first IronPython release that will
require this will be Beta 4 but it&#8217;ll start showing up in our source tree
sometime next week.&nbsp; <o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal>The reason for this change is that .NET 2.0 has a few bugs
which we&#8217;ve been working around until this point.&nbsp; There&#8217;s one
in particular, referencing generic fields on a type from dynamic methods, which
effects our public surface, performance, and compatibility with .NET 3.5
(w.r.t. LINQ Expression trees).&nbsp; As the DLR team continues their work this
has become more and more problematic and we&#8217;re now at the point where
they need to be able to move forward.&nbsp; <o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal>.NET 2.0 SP1 was released last November so we hope that this
gives plenty of time between it&#8217;s release and the final IronPython
release to enable most users to upgrade.&nbsp; Also anyone who has deployed
.NET 3.5 will also have .NET 2.0 SP1 installed so we&#8217;re hoping this isn&#8217;t
too high of a bar.<o:p></o:p></p>

<p class=MsoNormal><o:p>&nbsp;</o:p></p>

<p class=MsoNormal>If you have any questions or concerns please let us know.
Thanks!<o:p></o:p></p>

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