diff --git a/src/plugins/projectexplorer/kit.cpp b/src/plugins/projectexplorer/kit.cpp
index 03249ba7951..ace5407d198 100644
--- a/src/plugins/projectexplorer/kit.cpp
+++ b/src/plugins/projectexplorer/kit.cpp
@@ -53,6 +53,22 @@ const char ICON_KEY[] = "PE.Profile.Icon";
 
 namespace ProjectExplorer {
 
+// --------------------------------------------------------------------
+// Helper:
+// --------------------------------------------------------------------
+
+static QString cleanName(const QString &name)
+{
+    QString result = name;
+    result.replace(QRegExp("\\W"), QLatin1String("_"));
+    result.replace(QRegExp("_+"), "_"); // compact _
+    result.remove(QRegExp("^_*")); // remove leading _
+    result.remove(QRegExp("_+$")); // remove trailing _
+    if (result.isEmpty())
+        result = QLatin1String("unknown");
+    return result;
+}
+
 // -------------------------------------------------------------------------
 // KitPrivate
 // -------------------------------------------------------------------------
@@ -185,6 +201,22 @@ void Kit::setDisplayName(const QString &name)
     kitUpdated();
 }
 
+QString Kit::fileSystemFriendlyName() const
+{
+    QString name = cleanName(displayName());
+    foreach (Kit *i, KitManager::instance()->kits()) {
+        if (i == this)
+            continue;
+        if (name == cleanName(i->displayName())) {
+            // append part of the kit id: That should be unique enough;-)
+            // Leading { will be turned into _ which should be fine.
+            name = cleanName(name + QLatin1Char('_') + (id().toString().left(7)));
+            break;
+        }
+    }
+    return name;
+}
+
 bool Kit::isAutoDetected() const
 {
     return d->m_autodetected;
diff --git a/src/plugins/projectexplorer/kit.h b/src/plugins/projectexplorer/kit.h
index 82e303c0c14..d275fb59137 100644
--- a/src/plugins/projectexplorer/kit.h
+++ b/src/plugins/projectexplorer/kit.h
@@ -64,6 +64,8 @@ public:
     QString displayName() const;
     void setDisplayName(const QString &name);
 
+    QString fileSystemFriendlyName() const;
+
     bool isAutoDetected() const;
     Core::Id id() const;
 
diff --git a/src/plugins/qt4projectmanager/qt4project.cpp b/src/plugins/qt4projectmanager/qt4project.cpp
index eed22d62ae9..f9d33f6505f 100644
--- a/src/plugins/qt4projectmanager/qt4project.cpp
+++ b/src/plugins/qt4projectmanager/qt4project.cpp
@@ -1412,7 +1412,8 @@ QString Qt4Project::buildNameFor(const Kit *k)
 {
     if (!k)
         return QLatin1String("unknown");
-    return QString::fromLatin1(k->id().name()).mid(31, 6); // part of the UUID, should be pretty unique;-)
+
+    return k->fileSystemFriendlyName();
 }
 
 Target *Qt4Project::createTarget(Kit *k, const QList<BuildConfigurationInfo> &infoList)