Converting selected Rows to columns

Hi,

I have an excel file which looks like this :-

ID FIRST_NAME LAST_NAME 01/04/2013 02/05/2013
1 JOHN SMITH
2 ANDREW LIN
ID FIRST_NAME LAST_NAME 14/07/2013 21/10/2013
3 NEIL JOHNSON
4 ROBERT KALLIS


where the 2 dates are account open and close date.

What is want is to convert dates into columns until next header is encountered, it should look something like this :-

ID FIRST_NAME LAST_NAME 01/04/2013 02/05/2013
1 JOHN SMITH 01/04/2013 02/05/2013
2 ANDREW LIN 01/04/2013 02/05/2013
ID FIRST_NAME LAST_NAME 14/07/2013 21/10/2013
3 NEIL JOHNSON 14/07/2013 21/10/2013
4 ROBERT KALLIS 14/07/2013 21/10/2013

Please let me know if i am not clear enough.

Thanks in advance