Have somebody note the next situation :
Lets say that you have a form with a list that has
2 columns, my RowSourceType is set to 0-none,
and in the init event of my form I receive an
array that populates the list using the next code :

PARAMETER aMyArray
LOCAL x

FOR m.x=1 TO ALEN(aMyArray,1)
THISFORM.list1.addListItem(aMyArray(m.x,1),m.x,1)
THISFORM.list1.addListItem(aMyArray(m.x,2),m.x,2)
ENDFOR

I did that to populate the two columns of my list,
then Foxpro returned me an error:
'Not a numeric expression', in this line

THISFORM.list1.addListItem(aMyArray(m.x,1),m.x,1)

it doesn't recognize a memory variable, in this case
m.x, to know in which line of the list you want to
add the new item.
I needed to 'cheat' foxpro to make it work, I did
the next trick:
THISFORM.list1.addListItem(aMyArray(m.x,1),EVAL(STR(m.x)),1)

I used EVAL(STR(m.x)), so fox will think it has a
a numeric expression, but it doesn't let you use the
memory variable directly.
I'm using 3.0, I don't know if this was fixed in 3.0b,
I'm going to try it in 5.0 and see what happens.