Splitting Monthly requirements

Hi

I have created one requirement plan for 5 materials and for next year i.e for 12 months and now i want to split the monthly requirement on daily basis,

If i am selecting one material at a time in md61 and when i go to schedule line tab and then after pressing distribution over a period (F6) then i can split the requirement for specific material but if i am selecting 5 materials at a time then system only allows me to split one material at a time.

Can anybody let me know the procedure for splitting all the 5 material at a time. Else can anyone let me know the procedure of using MD67.

Thanks in advance.

Regards,

Anand.