Version:           [4.4 branch] r1088944 (using KDE 4.4.0)
Compiler:          gcc 4.4.3 
OS:                Linux
Installed from:    Compiled From Sources

This is probably a KIPI-Plugins issue, but I can't find the right component to use there.

When I get Gwenview to auto-rotate images, I get a lot of warnings about how they could not be rotated (with no further info).

Here is the console output for attempting to rotate 3 images.  The first is already in the correct orientation (and the dialog box says that it was rotated successfully), and the other two are not (the dialog box says that they could not be rotated.

gwenview(30527)/KEXIV2 KExiv2Iface::KExiv2::getImageOrientation: Orientation => Exif.Image.Orientation =>  1
gwenview(30527)/KIPI (general) KIPIJPEGLossLessPlugin::transformJPEG: Transforming with option  0   0
gwenview(30527)/KEXIV2 KExiv2Iface::KExiv2::setImageOrientation: Exif.Image.Orientation tag set to:  1
gwenview(30527)/KEXIV2 KExiv2Iface::KExiv2::save: File Extension:  "jpg"  is supported for writing mode
gwenview(30527)/KEXIV2 KExiv2Iface::KExiv2::getImageOrientation: Orientation => Exif.Image.Orientation =>  6
gwenview(30527)/KIPI (general) KIPIJPEGLossLessPlugin::transformJPEG: Transforming with option  0   5
QFile::setFileName: File (/tmp/kde-alex/gwenviewP30527kipiplugin-rotate.JPG) is already opened
gwenview(30527)/KEXIV2 KExiv2Iface::KExiv2::getImageOrientation: Orientation => Exif.Image.Orientation =>  8
gwenview(30527)/KIPI (general) KIPIJPEGLossLessPlugin::transformJPEG: Transforming with option  0   7
QFile::setFileName: File (/tmp/kde-alex/gwenviewL30527kipiplugin-rotate.JPG) is already opened
gwenview(30527)/kio (KDirModel) KDirModelPrivate::_k_slotRefreshItems: dataChanged( "[index for /home/alex/pics/digicam/Thing: 2010 Feb/P1000596.JPG]"  -  "[index for /home/alex/pics/digicam/Thing: 2010 Feb/P1000776.JPG]"