Hi Sue
Looks like you have found an incompatibility between the formatting characters used in the old style date format function (dtos()) and the new (d2s()).
Doing this: d2s(now(), "M/d/yyyy h:mm tt zzz")
produces: 1/30/2009 11:37 PM -08:00
The new AM/PM designator is "t", or "tt" for long form.
The time zone designator is "z" or "zz": the result is always the hour offset from GMT, not a code like "PST".
The new characters are all documented in the help, but the "a" is incorrectly shown in the expression editor.
HTH
Regards
Admin