What is the correct IE browser and document mode for the Sitecore 7.1 shell ?
Sitecore 7.0 IE10 Compat View / doc mode: IE5 quirks
Sitecore 7.1 IE10 / doc mode: Standards (?)
According to the Release Notes, Sitecore should now support IE in standard rendering mode:
All supported browsers now render the Sitecore Desktop and other Sitecore clients using "standards" mode. Previously, the Sitecore clients were rendered using "quirks mode" in Internet Explorer. (389935, 392576)
If that doesn't work for you, contact support to report it as a bug.