REGARDING RADIOBUTTON

HI GURUS,

I have 2 groups.in one group 2 radiobuttons,pdhplant,pp plant

in 2nd group , ihave 4 radio buttons,offspec,linespec,line1&line2.

my requirement is if i click,pdh plant then all the 2nd group radio buttons will disable mode& if i select pp plant then again

my 2nd group radiobuttons in actibe state.

how to achive , please help me.

thanks

subhasis