Excel 2007 : Need a formula or another method to change time in a sheet quickly

Hi,

I need to add 50mins to the time in the column below. For eaxmple:
28-03-09 7:44 needs to become 28-03-09 8:34

What you see below are all in one column. I have hundreds to update. Can someone give me a formula to do this quickly? Thanks

28-03-09 11:17
28-03-09 7:44
26-03-09 15:13
26-03-09 7:52
25-03-09 7:36
24-03-09 15:11
24-03-09 7:40
23-03-09 15:08
23-03-09 7:37
21-03-09 11:13
21-03-09 7:49
20-03-09 15:10
20-03-09 7:59
19-03-09 15:10
19-03-09 7:51
18-03-09 15:10
18-03-09 7:46
17-03-09 15:09
17-03-09 7:40
16-03-09 15:11
16-03-09 7:37

in a blank cell enter 0:50

copy this cell and then highlight all of your datetime values -> edit -> paste special -> operation: Add

Thank you for the quick response. But when I use the method above, the time does change, but the date disappear....Any tip for that?

I managed to do it. Thank you all for your prompt replies. It has been very helpful.