UNIX for Dummies Questions & Answers

Hello,
Using Solaris 10. Going to mirror disks with solstice disksuite. Documentation says I have to make both disks partitioned exactly the same before moving on.
Here's the layout of c1t0d0
Part Tag Flag Cylinders Size Blocks
0 root wm 1237 - 2473 6.00GB (1237/0/0) 12587712
1 swap wu 0 - 1236 6.00GB (1237/0/0) 12587712
2 backup wm 0 - 14086 68.35GB (14087/0/0) 143349312
3 unassigned wm 0 0 (0/0/0) 0
4 unassigned wm 0 0 (0/0/0) 0
5 var wm 2474 - 3710 6.00GB (1237/0/0) 12587712
6 unassigned wm 3711 - 14075 50.29GB (10365/0/0) 105474240
7 unassigned wm 14076 - 14086 54.66MB (11/0/0) 111936

I need to make c1t1d0 look just like it to do a mirror. I get to the last partition so my c1t1d0 looks like:
Part Tag Flag Cylinders Size Blocks
0 root wm 1237 - 2473 6.00GB (1237/0/0) 12587712
1 swap wu 0 - 1236 6.00GB (1237/0/0) 12587712
2 backup wu 0 - 14086 68.35GB (14087/0/0) 143349312
3 unassigned wm 0 0 (0/0/0) 0
4 unassigned wm 0 0 (0/0/0) 0
5 var wm 2474 - 3710 6.00GB (1237/0/0) 12587712
6 unassigned wm 3711 - 14075 50.29GB (10365/0/0) 105474240
7 unassigned wm 0 0 (0/0/0) 0

I go to 7 on c1t1d0 to make the last change and get the following:
partition> 7
Part Tag Flag Cylinders Size Blocks
7 unassigned wm 0 0 (0/0/0) 0

Enter partition id tag[unassigned]: unassigned
Enter partition permission flags[wm]: wm
Enter new starting cyl[0]: 14076
Enter partition size[0b, 0c, 14076e, 0.00mb, 0.00gb]: 54.66mb
`54.66mb' is out of range
Enter partition size[0b, 0c, 14076e, 0.00mb, 0.00gb]:

I can't imagine the two disks being different in size. Anyone ever seen 'out of range' before while partitioning?

Thanks in advance

Enter the size as 11 cylinders, not 54.66 MB. You are probably getting a rounding error.