diff --git a/lib/func.cpp b/lib/func.cpp
index 4c1db927..7c9ee1eb 100644
--- a/lib/func.cpp
+++ b/lib/func.cpp
@@ -221,6 +221,9 @@ const QString getDocDir()
 	QStringList docs;
 #ifdef DOCDIR
 	docs << QString(DOCDIR);
+#endif
+#ifdef INSTALL_DATA_PREFIX
+	docs << QString(INSTALL_DATA_PREFIX);
 #endif
 	docs += QStandardPaths::standardLocations(QStandardPaths::AppDataLocation);
 	foreach (docdir, docs) {
@@ -260,12 +263,21 @@ const QString getUserSettingsDir()
 
 const QString getI18nDir()
 {
-	QString qm = QStandardPaths::locate(QStandardPaths::AppDataLocation,
-		I18N_DIR "xca_de.qm");
+	static QString qm;
+	if (!qm.isEmpty())
+		return qm;
+#ifdef INSTALL_DATA_PREFIX
+	if (QFileInfo::exists(INSTALL_DATA_PREFIX "/xca_de.qm"))
+		qm = INSTALL_DATA_PREFIX "/xca_de.qm";
+#endif
+	if (qm.isEmpty())
+		qm = QStandardPaths::locate(QStandardPaths::AppDataLocation,
+			I18N_DIR "xca_de.qm");
 	if (qm.isEmpty())
 		qm = QCoreApplication::applicationDirPath() + "/xca_de.qm";
+	qm = QFileInfo(qm).path();
 	qDebug() << "QM" << qm;
-	return QFileInfo(qm).path();
+	return qm;
 }
 
 void migrateOldPaths()
diff --git a/lib/oid.cpp b/lib/oid.cpp
index a879ad80..dea02708 100644
--- a/lib/oid.cpp
+++ b/lib/oid.cpp
@@ -25,6 +25,16 @@ NIDlist distname_nid;
 QMap<QString,const char*> oid_name_clash;
 QMap<QString,int> oid_lower_map;
 
+static QStringList searchdirs()
+{
+	QStringList dirs = QStandardPaths::standardLocations(
+				QStandardPaths::AppDataLocation);
+#ifdef INSTALL_DATA_PREFIX
+	dirs << QString(INSTALL_DATA_PREFIX);
+#endif
+	return dirs;
+}
+
 static void addToLowerMap(int nid)
 {
 	QString n = OBJ_nid2sn(nid);
@@ -120,7 +130,7 @@ static void readOIDs(const QString &fname)
 	int line = 0;
 	QFile file(fname);
 	if (!file.open(QIODevice::ReadOnly))
-                return;
+		return;
 	qDebug() << "Read additional OIDs from" << fname;
 	QTextStream in(&file);
 	while (!in.atEnd()) {
@@ -171,8 +181,7 @@ static NIDlist read_nidlist(const QString &name)
 {
 	NIDlist nl;
 
-	foreach(QString d, QStandardPaths::standardLocations(
-				QStandardPaths::AppDataLocation))
+	foreach(QString d, searchdirs())
 	{
 		nl = readNIDlist(d + "/" + name);
 		qDebug() << "Read" << nl.count() << "NIDs from"
@@ -191,8 +200,7 @@ void initOIDs()
 		addToLowerMap(i);
 	ign_openssl_error();
 
-	foreach(QString d, QStandardPaths::standardLocations(
-				QStandardPaths::AppDataLocation))
+	foreach(QString d, searchdirs())
 		readOIDs(d + "/oids.txt");
 
 	extkeyuse_nid = read_nidlist("eku.txt");
diff --git a/local.h.in b/local.h.in
index e2503e68..ace149a5 100644
--- a/local.h.in
+++ b/local.h.in
@@ -11,3 +11,8 @@
 
 /* Build an AppStore compliant version */
 #cmakedefine APPSTORE_COMPLIANT
+
+/* Install PREFIX (linux only) */
+#if defined Q_OS_UNIX && ! defined Q_OS_MACOS
+#define INSTALL_DATA_PREFIX "@CMAKE_INSTALL_PREFIX@/share/xca"
+#endif