split a string into line

Hi Gurus,

I want to split a particular string into lines. I have a string concatenate by values separated by semicoloumn.While print this string in smartform have to print into several rows. but I dont know the exctact length of the field concatenated into a string. My requirement is to split the string into lines but each line have to end with semicoloum, that is all values have to end in a particlar line should not continue on a next line.

Foe eg:

Var1 = 'abcdef'

var2 = 'qwert'

var3 = 'asdfghjkl'.

String = var1;var2;var3.

in printform have to print in a line with length 20 means

Output should be in the below format:

line1 - abcedf;qwert;

line2 - asdfghjkl.

Even there is some space in line1 to hold var3, but i want it in a next line.

Thanks in advance.

Reagrds,

Bhuvana.