How about this?

**Excel 2007**
<colgroup><col><col><col><col></colgroup><thead>

</thead><tbody>

[TD="align: center"]1[/TD]

</tbody>

**Sheet1**

[TABLE="width: 85%"]

<tbody>[TR]

[TD]

**Worksheet Formulas**[TABLE="width: 100%"]

<thead>[TR="bgcolor: #E0E0F0"]

[TH="width: 10"]Cell[/TH]

[TH="align: left"]Formula[/TH]

[/TR]

</thead><tbody>[TR]

[TH="width: 10, bgcolor: #E0E0F0"]B1[/TH]

[TD="align: left"]=LEFT(

A1,FIND(":",A1)-1)[/TD]

[/TR]

[TR]

[TH="width: 10, bgcolor: #E0E0F0"]C1[/TH]

[TD="align: left"]=RIGHT(

A1,LEN(A1)-FIND(":",A1))[/TD]

[/TR]

</tbody>[/TABLE]

[/TD]

[/TR]

</tbody>[/TABLE]