Dumb sort question

[jbv]

Hi everybody,

Sorting a variable made of various lines with several items
in each line with the sort command is easy :

    sort lines of Myvariable by item 2 of each


But how can I sort a variable featuring 4 lines with several
hundreds of items in each, so that (for instance) items of
line 4 are sorted numeric ascending, and (that's important)
items of other lines being moved according to the new
position of each item of line 4 ?

For instance :
    line 1 :    b,d,c,a
    line 2 :    2,4,3,1

after sorting line 2, the content would become :
    line 1 :    a,b,c,d
    line 2 :    1,2,3,4

I have the feeling this can't be done in MC, while I remember
doing it in OMO using the spreadsheet control...

Thanks for any suggestion.
JB

P.S. I need to do it FAST on large variables, therefore a repeat
loop won't do.