so, Frank Wiles was right!!! it was a time issue (which i totally don't understand).

now, i'm no longer desperate, but i am perplexed!!

all i had to do, in the end, was change to a +2h expiration time, instead of +1h, BUT the wierd thing is that when i open the cookie that is set in IE, the expiration time is actually one hour from the time i set it - why is IE chopping off an hour???

thanks to all for the helpful suggestions, and if anyone has an idea about why this odd behavior - i'd love to know the answer! no rush though!!