Access: time format question

I have a text box on a form where I would like to use a time format that shows hours greater than “23:59” (i.e. hours worked in a week = 40:00). Unfortunately, when I use hh:mm format, I get “15:00”) is there an easy work around for this?

In Excel, I use the time format: [h]:mm:ss
…but access doesn’t like it when I put that in the format property.

Thanks in advance for your help!