If you are using style sheet, write following styles to the label

<div style="width: 149px; white-space:normal;">

<asp:Label CssClass="V10BBrown" ID="Label5" runat="server" Text=’<%# Bind("Desc1")%>‘ Width="149px" />

</div>

Others are not importent, but the "White-space: normal" is importent. But make sure your text have space in middle

for example, it is not work this type of text "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"

it is work this type of text "xxxxxx xxxxxxxx xxxxxxxxx xxxx xxx xxx xxx"

 

Cheers……………..!