IE9: Designer is not fully loaded

Description of problem:
I tried jBPM Designer with IE9 and it was not loaded. I was waiting for 5 minutes without any results.

When I tried different browsers (Chrome, Firefox) with same instance of BPMS then the designer works without problems.

Version-Release number of selected component (if applicable):
6.0.2 GA BPMS and 6.1.0 SNAPSHOT BPMS

How reproducible:
every time when you open any process from repository in IE9. It seems that IE10 and IE 11 works.

Actual results:
Designer is gray, loading dialog and partially loaded toolbar are present.

Expected results:
Fully loaded Designer.

Additional info:
Please, add commits for both product's versions (6.0.2 and 6.1.x).