Admin option to easily alter time/date of post at time of post?

[mkdevo]

i want my admins to be able to post a new thread, but to make the date/time stamp something in the past, so the thread doesn't show up as new.

i know i can change the date/time on the backend, but it's kind of a pain, especially with the unix time conversions.

i'd like to be able to post a new thread, and have the option (for admins only) to enter the date and time to be displayed for that thread.

is something like this available?