Access 2003 Combo Box Updating via VB Code

Hey there guys,

got a combo box on getting its values from a table. if value is not in the table then the user enters the value in a textbox and clicks a command button to enter the new value into the table. now i need to be able to refresh/requery the combo box so the new value appears there without closing and reopening the form. Please help with this, been racking my brains for the past three days and have now spent far to much time on one little problem.

Please give me an example of code so I can have a look and learn.