Rowspan in Webgrid in MVC

Question

 How to display webgrid as shown below in MVC 3.

h1   |   h2  |  h3
-------------------
R11  |  R12  |  R13
-----|-------|------
     |  R22  |  R23
     |-------|------
     |  R32  |  R33
-------------------
R42  |  R41  |  R43
-----|-------|------
     |  R44  |  R45

Middle colmn and 3 rd column spans multiple rows.