A colleague of mine was once denied entry into South Africa because his passport did not have a "clean" page in it for the entry stamp. His passport had just a single tiny stamp on several pages - but one of them had to be completely clean. Bizarre.

The problem was solved by a KLM agent who took the issue to an immigration supervisor - otherwise he would have to take him back on the return flight and no doubt pay a fine...

The South African entry stamp turned out to be a tiny sticker that easily fit in his passport - on any number of "non-clean" page...

Back on topic: I feel your frustration re. CAL.