William Roberts <williamr@symbian.org> [Wed, 07 Jul 2010 22:00:46 +0100] rev 197
Revised fix for bug 3111 - switch to usrt4_0.lib, which is exported unconditionally
usrt3_1.lib is invisibly exported by an FLM, so in platform builds this failed with "No rule to make usrt3_1.dso"