when has crystal started?

[electrolust]

My project is an MSP430G2121 with external 32768 crystal.  How do I know when the crystal has started/stabilized?

All example code I can find tests OFIFG in a loop, but also all this example code is using LFXT1 as the clock source for MCLK.  Does the OFIFG flag work when MCLK is running on the DCO?  I suppose I can run off of LFXT1 until I determine if the crystal has started, then switch it to DCO, but just out of curiosity I wonder if this is required.  The manual (slau144) isn't exactly clear on the topic.

Obviously I can test this easily but I won't have access to my test board for another week.