If you could, please post some of your code where you are splitting and trying to loop through the array. That would help us to help you.
As a stab in the dark though...
<%
txtString = "This,is,my,string"
myarray = split(txtString, ",")
for x = lbound(myarray) to ubound(myarray)
response.write myarray(x) & "<BR>"
next
%>