diff --git a/server/kernel/src/Transformation/TransformationAbstract.cpp b/server/kernel/src/Transformation/TransformationAbstract.cpp
index 1deb7d4..afbaef0 100644
--- a/server/kernel/src/Transformation/TransformationAbstract.cpp
+++ b/server/kernel/src/Transformation/TransformationAbstract.cpp
@@ -56,13 +56,13 @@ namespace TREPS
 			bool noTrans = (strcmp(srcFrame,dstFrame) == 0);
 
 			//set frames
-			if (!this->checkFrame(srcFrame) && !noTrans)
+			if (!noTrans && !this->checkFrame(srcFrame))
 			{
 				LOG4CXX_ERROR(this->app->getLog()->getPtr(),"Unknown frame for this engine : " << srcFrame);
 				return false;
 			}
 
-			if (!this->checkFrame(dstFrame) && !noTrans)
+			if (!noTrans && !this->checkFrame(dstFrame))
 			{
 				LOG4CXX_ERROR(this->app->getLog()->getPtr(),"Unknown frame for this engine : " << dstFrame);
 				return false;
--
libgit2 0.21.2