I work in an IBM shop running RPG code; to me it’s either numeric or it’s alphanumeric. (Don’t bring up packed decimals and such. I’m trying to make a point here.) So I’d probably have the same issues as Coyote did:
A web site on which I was registering said “Your password must be alpha-numeric and a minimum of 6 characters.” I had an argument about this language with the customer service agent, but I may be wrong. I would interpret this as meaning that all the characters in the password must be from the alpha-numeric set, as opposed to, say, symbol characters. Therefore “asdfasdf”, “12345678”, and “asdf1234” would all meet the stated test. The customer service agent said that I was totally wrong, and went so far as to inform me their web designer has a PhD in English. Her contention was that alpha-numeric clearly means “must contain both a minimum of one alphabetical character and at least one numeric character.” In my example above, only “asdf1234” would therefore qualify.
If nothing else, this should establish, once and for all, the value of a PhD in English.
Our merchant bank demands eight characters at a minimum, of which only six can be good ol’ letters, and at least one of them, though not all of them, must be in uppercase; in addition, you must have a digit and a punctuation mark of some sort. Perhaps remarkably, it helps to be semi-fluent in 1337-speak.