diff --git a/simgear/package/CatalogTest.cxx b/simgear/package/CatalogTest.cxx
index 6a4446c0..f61763c2 100644
--- a/simgear/package/CatalogTest.cxx
+++ b/simgear/package/CatalogTest.cxx
@@ -92,6 +92,11 @@ public:
                 path = ss.str();
             }
         }
+        
+        // return zip data for this computed URL
+        if (path.find("/catalogTest1/movies") == 0) {
+            path = "/catalogTest1/movies-data.zip";
+        }
 
         localPath.append(path);
 
@@ -152,7 +157,7 @@ int parseTest()
     SG_CHECK_EQUAL(cat->description(), "First test catalog");
 
 // check the packages too
-    SG_CHECK_EQUAL(cat->packages().size(), 4);
+    SG_CHECK_EQUAL(cat->packages().size(), 5);
 
     pkg::PackageRef p1 = cat->packages().front();
     SG_CHECK_EQUAL(p1->catalog(), cat.ptr());
@@ -326,7 +331,7 @@ void testAddCatalog(HTTP::Client* cl)
     p.append("org.flightgear.test.catalog1");
     p.append("catalog.xml");
     SG_VERIFY(p.exists());
-    SG_CHECK_EQUAL(root->allPackages().size(), 4);
+    SG_CHECK_EQUAL(root->allPackages().size(), 5);
     SG_CHECK_EQUAL(root->catalogs().size(), 1);
 
     pkg::PackageRef p1 = root->getPackageById("alpha");
@@ -559,6 +564,43 @@ void testInstallTarPackage(HTTP::Client* cl)
     SG_VERIFY(p.exists());
 }
 
+void testInstallArchiveType(HTTP::Client* cl)
+{
+    global_catalogVersion = 0;
+    SGPath rootPath(simgear::Dir::current().path());
+    rootPath.append("pkg_install_archive_type");
+    simgear::Dir pd(rootPath);
+    pd.removeChildren();
+    
+    pkg::RootRef root(new pkg::Root(rootPath, "8.1.2"));
+    // specify a test dir
+    root->setHTTPClient(cl);
+    
+    pkg::CatalogRef c = pkg::Catalog::createFromUrl(root.ptr(), "http://localhost:2000/catalogTest1/catalog.xml");
+    waitForUpdateComplete(cl, root);
+    
+    pkg::PackageRef p1 = root->getPackageById("org.flightgear.test.catalog1.movies");
+    SG_CHECK_EQUAL(p1->id(), "movies");
+    pkg::InstallRef ins = p1->install();
+    
+    SG_VERIFY(ins->isQueued());
+    
+    waitForUpdateComplete(cl, root);
+    SG_VERIFY(p1->isInstalled());
+    SG_VERIFY(p1->existingInstall() == ins);
+    
+    // verify on disk state
+    SGPath p(rootPath);
+    p.append("org.flightgear.test.catalog1");
+    p.append("Aircraft");
+    p.append("movies_6789"); // FIXME once archive-dir support is decided
+    
+    SG_CHECK_EQUAL(p, ins->path());
+    
+    p.append("movie-list.json");
+    SG_VERIFY(p.exists());
+}
+
 void testDisableDueToVersion(HTTP::Client* cl)
 {
     global_catalogVersion = 0;
@@ -915,7 +957,9 @@ int main(int argc, char* argv[])
     testRefreshCatalog(&cl);
 
     testInstallTarPackage(&cl);
-
+    
+    testInstallArchiveType(&cl);
+    
     testDisableDueToVersion(&cl);
     
     testOfflineMode(&cl);
diff --git a/simgear/package/Install.cxx b/simgear/package/Install.cxx
index 7e22f0f2..96cd11e6 100644
--- a/simgear/package/Install.cxx
+++ b/simgear/package/Install.cxx
@@ -57,6 +57,10 @@ public:
             throw sg_exception("no package download URLs");
         }
 
+        if (m_owner->package()->properties()->hasChild("archive-type")) {
+            setArchiveTypeFromExtension(m_owner->package()->properties()->getStringValue("archive-type"));
+        }
+        
         // TODO randomise order of m_urls
 
         m_extractPath = aOwner->path().dir();
@@ -196,7 +200,22 @@ protected:
     }
 
 private:
-
+    void setArchiveTypeFromExtension(const std::string& ext)
+    {
+        if (ext.empty())
+            return;
+        
+        if (ext == "zip") {
+            m_archiveType = ZIP;
+            return;
+        }
+        
+        if ((ext == "tar.gz") || (ext == "tgz")) {
+            m_archiveType = TAR_GZ;
+            return;
+        }
+    }
+    
     void extractCurrentFile(unzFile zip, char* buffer, size_t bufferSize)
     {
         unz_file_info fileInfo;
@@ -262,14 +281,22 @@ private:
     {
         const std::string u(url());
         const size_t ul(u.length());
-        if (u.rfind(".zip") == (ul - 4)) {
-            return extractUnzip();
+        
+        if (m_archiveType == AUTO_DETECT) {
+            if (u.rfind(".zip") == (ul - 4)) {
+                m_archiveType = ZIP;
+            } else if (u.rfind(".tar.gz") == (ul - 7)) {
+                m_archiveType = TAR_GZ;
+            }
+            // we will fall through to the error case now
         }
-
-        if (u.rfind(".tar.gz") == (ul - 7)) {
+        
+        if (m_archiveType == ZIP) {
+            return extractUnzip();
+        } else if (m_archiveType == TAR_GZ) {
             return extractTar();
         }
-
+        
         SG_LOG(SG_IO, SG_WARN, "unsupported archive format:" << u);
         return false;
     }
@@ -330,7 +357,14 @@ private:
         m_owner->installResult(aReason);
     }
 
+    enum ArchiveType {
+        AUTO_DETECT = 0,
+        ZIP,
+        TAR_GZ
+    };
+    
     InstallRef m_owner;
+    ArchiveType m_archiveType = AUTO_DETECT;
     string_list m_urls;
     SG_MD5_CTX m_md5;
     std::string m_buffer;
diff --git a/simgear/package/catalogTest1/catalog.xml b/simgear/package/catalogTest1/catalog.xml
index 26fb7025..1b8b7b59 100644
--- a/simgear/package/catalogTest1/catalog.xml
+++ b/simgear/package/catalogTest1/catalog.xml
@@ -177,4 +177,17 @@
         <file-size-bytes>360</file-size-bytes>
         <md5>acf9eb89cf396eb42f8823d9cdf17584</md5>
     </package>
+
+
+    <package>
+        <id>movies</id>
+        <name>movies files for test catalog aircraft</name>
+        <revision>10</revision>
+        <dir>movies_6789</dir>
+        <!-- url has no file extension, instead we set arcive-type -->
+        <url>http://localhost:2000/catalogTest1/movies?wierd=foo;bar=thing</url>
+        <archive-type>zip</archive-type>
+        <file-size-bytes>232</file-size-bytes>
+        <md5>e5f89c3f1ed1bdda16174c868f3c7b30</md5>
+    </package>
 </PropertyList>
diff --git a/simgear/package/catalogTest1/movies-data.zip b/simgear/package/catalogTest1/movies-data.zip
new file mode 100644
index 00000000..695ec1e7
Binary files /dev/null and b/simgear/package/catalogTest1/movies-data.zip differ
diff --git a/simgear/package/catalogTest1/movies_6789/movie-list.json b/simgear/package/catalogTest1/movies_6789/movie-list.json
new file mode 100644
index 00000000..13be6b27
--- /dev/null
+++ b/simgear/package/catalogTest1/movies_6789/movie-list.json
@@ -0,0 +1,3 @@
+{
+    "id": "awesomething"
+}
\ No newline at end of file