proposed fix

gistfile1.diff

diff --git a/Tools/BuildSlaveSupport/build.webkit.org-config/master.cfg b/Tools/BuildSlaveSupport/build.webkit.org-config/master.cfg
index 1d889bc..add7ffd 100644
--- a/Tools/BuildSlaveSupport/build.webkit.org-config/master.cfg
+++ b/Tools/BuildSlaveSupport/build.webkit.org-config/master.cfg
@@ -553,11 +553,8 @@ class RunQtAPITests(shell.Test):
     descriptionDone = ["API tests"]
     command = ["python", "./Tools/Scripts/run-qtwebkit-tests",
                "--output-file=qt-unit-tests.html", "--do-not-open-results", "--timeout=120",
-               WithProperties("WebKitBuild/%(configuration_pretty)s/Source/WebKit/qt/tests/")]
-
-    def start(self):
-        self.setProperty("configuration_pretty", self.getProperty("configuration").title())
-        return shell.Test.start(self)
+               WithProperties("WebKitBuild/%(configuration_pretty)s/Source/WebKit/qt/tests/", configuration_pretty=lambda build: build.getProperty("configuration").title())
+                ]
 
     def commandComplete(self, cmd):
         shell.Test.commandComplete(self, cmd)
diff --git a/Tools/ChangeLog b/Tools/ChangeLog
index 8aed577..21750fe 100644
--- a/Tools/ChangeLog
+++ b/Tools/ChangeLog
@@ -1,3 +1,15 @@
+2012-03-05  Kristóf Kosztyó  <kkristof@inf.u-szeged.hu>
+
+        Qt API test buildstep throws exception after buildmaster update
+        https://bugs.webkit.org/show_bug.cgi?id=80249
+
+        This patch based on Peter Gal's work.
+
+        Reviewed by NOBODY (OOPS!).
+
+        * BuildSlaveSupport/build.webkit.org-config/master.cfg:
+        (RunQtAPITests):
+
 2012-03-05  Alexander Færøy  <alexander.faeroy@nokia.com>
 
         Unreviewed. Add myself to committer list.