Portability improvement : if unsetenv doesn't exist, use putenv
Portability improvement : if unsetenv doesn't exist, use putenv

svn path=/trunk/kdenetwork/kmail/; revision=10168

lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi