ASSERT: make sure you have an application running on OpenShift (ev. create one)
EXEC: in OpenShift Explorer: pick Edit Embedded Cartridges... in the context menu of your application
EXEC: check mysql-5.1 and hit Finish
EXEC: in OpenShift Explorer: unfold your application and select the freshly embedded mysql-cartridge
EXEC: Open Properties View (Ctrl+3->Properties)
Result:
Properties view is empty
After embedding mysql and clicking on embedded mysql cartridge: