Hi,
there is a problem with the new invisiprim rendering in deferred mode in today's 1.26.5.9. Screenshot attached. Notice that the skin seems to be kind of (but not really) transparent. This happens for sky, water and I think shiny objects that are behind the skin.
It's a good thing that you added a switch to disable this feature.

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Cool VL Viewer 1.26.5 (9) Sep 15 2012 12:19:46 (Cool VL Viewer)
Release Notes
You are at 188772.4, 356270.8, 24.7 in The Connection located at sim3544.agni.lindenlab.com (216.82.19.151:13000)
Second Life Server 12.09.04.264357
Release Notes: Retrieving...
CPU: Intel(R) Core(TM) i7 CPU X 980 @ 3.33GHz (3337.55 MHz)
Memory: 12280 MB
OS Version: Microsoft Windows 7 64-bit Service Pack 1 (Build 7601)
Graphics Card Vendor: NVIDIA Corporation
Graphics Card: GeForce GTX 580/PCIe/SSE2
Windows Graphics Driver Version: 9.18.0013.0479
OpenGL Version: 4.2.0
libcurl Version: libcurl/7.21.1 OpenSSL/0.9.8q zlib/1.2.5 c-ares/1.7.1
J2C Decoder Version: KDU
Audio Driver Version: FMOD version 3.750000
Qt Webkit Version: 4.7.1 (version number hard-coded)
Packets Lost: 0/8212 (0.0%)
Built with MSVC version 1600
Compile flags used for this build:
-DLL_RELEASE=1 -DLL_RELEASE_FOR_DOWNLOAD=1 -DLL_SEND_CRASH_REPORTS=1 -DNDEBUG /O2 /Oi /arch:SSE2 /MD /MP -D_SECURE_STL=0 -D_HAS_ITERATOR_DEBUGGING=0 /DWIN32 /D_WINDOWS /W3 /EHsc /GR /Oy- /GS /arch:SSE2 /fp:fast /TP /W2 /Zc:forScope /Zc:wchar_t- /c /nologo /DLL_USE_TCMALLOC=1 /DLL_WINDOWS=1 /D_SECURE_SCL=0 /DDOM_DYNAMIC /DUNICODE /D_UNICODE /DWINVER=0x0501 /D_WIN32_WINNT=0x0501 /DCARES_STATICLIB /DLIB_NDOF=1