I have been trying to replace our second level cache interface to use infinispan as second-level cache with hibernate. I followed
http://community.jboss.org/wiki/UsingInfinispanasJPAHibernateSecondLevelCacheProvider

See: org.hibernate.cache.infinispan.entity
But lamentably, my code fails since only read-only and transactional access types
for entity and collections have been implemented.

Is there any plan to support nonstrict-read-write and read-write? If so, when?
Any alternative?

Infinispan as 2L cache for Hibernate is designed to be transactional second-level implementation
(for this reason you must also use JTA),
therefore the only supported access types are read-only and transactional.
As far as I know there is no reason and therefore no plan to support nonstrict-read-write and read-write.
This because generally the tendency goes towards transactional access.
Also EHCache recently is doing efforts to support transactional access.
The solution in you case is simple: use transactional access instead to nonstrict-read-write and read-write.