Is it ok to put glass in microwave?

i have a glass container filled with mazet chocolate i need a way to warm it up to get it out but someyone told e i cant put i tin the microwave…. the top tho says ATTENTION:MICROWAVE INTESITY CAN VARY PLEASE CHECK AFTER 1 MINUTE.

so can i put this in the microwave?
http://www.igourmet.com/images/products/…