[eluser]dcheslow[/eluser]
Fixed!
Lesson: never overlook the possibility that there are TWO errors.
I was, in fact, running out of memory.
While solving another bug I had overwritten php.ini with a version that had 'Display-errors = Off'... ergo, no visible feedback on the error. DOH!
Thanks to all who responded! ... and Happy New Year!
=dave=