<b>Solution found!</b>
<p>
After basically two days of constant debugging by removing and adding functionality piece by piece, I've figured out what caused the problem.
</p>
<p>
As I've stated earlier, we create a StypeMap based on the default styles of the Vector-layer and extended with our custom values. While debugging, I noticed that if the StyleMap used only the default styles of the Vector-layer, the SelectFeature-control would function in all versions of Internet Explorer. But if we added our custom styles, the SelectFeature-control would fail. So why was this?
</p>
<p>
The style-property that was causing the problem was the <b>rotation</b>-property. We added this to the styles with a value of '0', i.e. no rotation as the default value for the property. However, this caused our features to not be selectable when using Internenet Explorer versions older than 9 (verified using IE9 CV, IE8, IE7). Everything works great in FireFox and Chrome though!
</p>
<p>
Simply removing the property from the styles solved the problem!
</p>
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View this message in context: <a href="http://osgeo-org.1560.n6.nabble.com/SelectFeature-when-using-IE-9-or-IE9-Compatibility-View-tp4368621p4379406.html">Re: SelectFeature when using IE<9 or IE9 Compatibility View</a><br/>
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