In order to address several issues with Second Life 1.9.0, we have just posted the latest version as an optional update. It will become a mandatory download in the next day or two. For now, we recommend upgrading as soon as possible to resolve the following issues:
Release Notes for Second Life 1.9.0(17) Mar 20, 2006
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* IMs containing Unicode characters will once again go directly from sender to recipient correctly
* Upload Texture preview once again contains avatar "mannequin"
* Alt-Zoom from vehicle no longer stops scroll wheel from working
* Version number now appears on the Second Life startup screen
* Resolved an issue where only High level terrain texture could be seen in a region
* Added ability to return to region's default sun position in World > Force Sun
* Added Midnight option to World > Force Sun menu
* Resolved several server- and client-side crash issues