Malaysia's National Fatwa Council has issued a fatwa declaring the use of electronic cigarettes as 'haram' or forbidden for Muslims.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/malaysian-muslim-clerics-issue-fatwa-against-e-cigarettes
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/international-business-times
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/smoking
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/malaysia
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-effects