What is the right workflow setting to make setting "Time spent" field value when resolving an issue compulsory? Google serch says that should be a transition Validation on "Field Compulsory", but there is no such Validation, only "Field value changed", which doesn't seem to work.
Here's how it looks like now - still doesn't work: http://cl.ly/image/402w1F1n2V0z
Would appreciate some help here.