I have baked many sheet cakes in 9 x 13 glass pans with no problem. As someone said, lower the temp. 25 degrees. They may cook a few minutes more or less than in a conventional metal 9 x 13 pan, but just test by the toothpick method or pressing lightly on the top of the cake to make sure it is solid.
You should have no problems. It's done all the time.