Unicode string and metakit database

[Tony]

I write a database application with Metakit. My script is like the
following:
...
vw = db.getas("t1[no:I,ch:S,code1:S,code2:S]")
...
*vw.append(no=i,ch=x,code1=y[0],code2=y[1])
...
But errors occured on "*" and it displayed "TypeError: not a Python
string".
x, y[0], y[1] are unicode strings. Doesn't Metakit support unicode or
else?

Thanks a lot!