The corp travel agent at my previous employer always insisted on using my full spanish name on my boarding passes, while all of my US and PR ID's use my name in US format.

It created problems at DFW and ATL once each, when the boarding pass showed Lastname1Lastname2 (no space), Firstname MI and my ID was Lastname1, Firstname. I'd call for a sup... I got lucky at DFW, where the supervisor was of hispanic origin and let me through after I explained- but the second time I had to get re-ticketed.