Lakmal Silva wrote:

I'm investigating the latest Internet Drafts of the
IETF related to IDNAs (International Domain Names) and
how they are going to effect Sinhala domain names. I
have a question weather we need to use ZWJ and ZWNJ
for Sinhala.  Any thoughts on this?
Yes. ZWJ (200D) is needed for Sinhala (but not ZWNJ).

According to the IDNAbis drafts, this character is defined as context-dependent, and needs a rule which says it is OK to allow it. These rules are currently not defined in IDNAbis, but would be taken from the unicode documentation (see below) which specifically mentions the "sri" issue.

I will keep monitoring the drafts, and check if they include the applicable rule.

for more information, see:

excerpt from

B. ZWJ in the following context:In a conjunct context. That is, a sequence of the form: