Unfortunately, the problem is a bit more complex than it looks. Internally, IE relies on the "zoom" property to implement its zooming functionality. This has an adverse side-effect - it turns the layout on all elements on the page and this in turn leads to all kinds of side-effects. You can read more about this problem here
As far as we know only Opera implements zooming without breaking the page layout.
The zoom issue is especially difficult, as there is no documentation whatsoever on the effects it causes to the page layout. Ideally, it should not cause any, but obviously this is not the case. There are many reports for problems related to this feature, for example:
We are researching the problem, but I cannot guarantee when and if it will be entirely resolved.
the Telerik team