The UTC has posted a new Public Review Issue regarding a proposal to specify optional conjuncts in Malayalam. http://www.unicode.org/review/pri250/
In Malayalam there are two prevailing orthographies, traditional and reformed. Both are written using the same Malayalam character set. The difference between them is typically manifested only by the font. Traditional orthography accommodates more full conjuncts, while the reformed orthography would use visibile virama (Chandrakkala) separated sequences for many of those full conjuncts.
This proposal specifies the further use of ZWJ and ZWNJ in sequences in the Malayalam script to indicate preferences for optional display of conjuncts. Such sequences are intended to indicate the preferences, both for rendering systems that support the reformed Malayalam orthography and for systems that support the traditional Malayalam orthography.
The UTC is seeking feedback on this proposal, regarding its advisability and potential impacts on implementations, as well as any suggestions for alternative approaches to the issues raised in the background document.http://unicode-inc.blogspot.com/2013/03/specifying-optional-conjuncts-in.html