Solaris

Check the timestamp. Was this error before you labelled the disk?
And y dont u do the copying of partition table the manual way as seg told? using the format utility,,

OK, so,
1: we all know the prtvtoc/fmthard command is not suitable when dealing with drives of different sizes.
2: I believe you've admitted that you understand how to set partition tables manually using the format command

I am left to guess that you:
were hoping to save a little time by using prtvtoc/fmthard instead of format
OR
want to figure out how to automate the process of setting partition tables in which case you can do so with the format command and the '-f' option (details in the man page).

This waring is there on the system before also as " wrong magic number" which now is coming with "corrupt lable; wrong magic number "

doesn't matter, its normal

I did manual slicing . Do i have to newfs these slices before putting them into volumes

Go ahead and newfs the slice.