Ramon says, I'm afraid I don't - but given the current situations, I'd suggest anyone that could help would also be wondering which version of QGIS you were using and on which operating system. The Qgis version is 1.6.0 also, the result is same on GRASS (tcl/tk) 6.4 RC1, performed on WinXP SP3 on a core2Duo machine. regards, Ambrish Dhaka