Base64 photo property

HI,

If I insert a photo in vCard with BASE64 format, is there any 
restriction on the line length of it?

Cos' I found that in some mobile phone, it requires the base64 content 
with linelength as 75 in every line of base64 encoding, but with no LWSP 
char,

Do I need to consider the line length of base64 content?
If so,
Do I need to add a LWSP before the CRLF when deal with a long base64 
content?


Thx

Regards,
Jacky Cheung