AutoCAD 2013 :: Does Support Multiple Lines Of Vertical Setting On Mtext

I guess it does NOT support it because it seems that it does NOT work properly. For example, in case of multiple lines of “Horizontal” setting, it works properly like followings. But in case of multiple lines of “Vertical” setting, it does NOT work properly like followings.

Configure of “Horizontal”:
ABC
DEF
GHI

Configure of “Vertical”:
ABC DEF GHI

In my perspective, it should go downward like followings.

In my “perspective” of Vertical”:
A
B
C

D
E
F

G
H
I

We are making application software for importing DXF file from AutoCAD. If AutoCAD does not support multiple lines of vertical setting on mtex, our software also should not support it, I think. I want to know the specification for multiple lines of vertical setting of AutoCAD.