diff --git a/src/main/java/org/gcube/vomanagement/usermanagement/impl/ws/LiferayWSUserManager.java b/src/main/java/org/gcube/vomanagement/usermanagement/impl/ws/LiferayWSUserManager.java
index e8bce76..37b49c3 100644
--- a/src/main/java/org/gcube/vomanagement/usermanagement/impl/ws/LiferayWSUserManager.java
+++ b/src/main/java/org/gcube/vomanagement/usermanagement/impl/ws/LiferayWSUserManager.java
@@ -51,6 +51,11 @@ import com.liferay.portal.kernel.exception.SystemException;
  */
 public class LiferayWSUserManager implements UserManager{
 
+	// save host/port and schema
+	private String schema;
+	private String host;
+	private int port;
+
 	// These properties are needed to save authentication credentials once.
 	private HttpClientContext localContext;
 	private CredentialsProvider credsProvider;
@@ -89,6 +94,10 @@ public class LiferayWSUserManager implements UserManager{
 	 */
 	public LiferayWSUserManager(String user, String password, String host, String schema, int port) throws Exception{
 
+		this.host = host;
+		this.port = port;
+		this.schema = schema;
+
 		target = new HttpHost(host, port, schema);
 		credsProvider = new BasicCredentialsProvider();
 		credsProvider.setCredentials(
@@ -206,9 +215,9 @@ public class LiferayWSUserManager implements UserManager{
 		}
 		return null;
 	}
-	
+
 	/**
-	 * Evaluate the user's avatar url path (relative)
+	 * Evaluate the user's avatar url path (absolute!)
 	 * @param userUuid
 	 * @param portraitId
 	 * @return
@@ -216,15 +225,17 @@ public class LiferayWSUserManager implements UserManager{
 	 * @throws NoSuchAlgorithmException
 	 */
 	private String getUserAvatarAbsoluteURL(String userUuid, long portraitId) throws UnsupportedEncodingException, NoSuchAlgorithmException{
-		
+
 		// url looks like LIFERAY_PORTAL/image/user_male_portrait?img_id=21125690&img_id_token=aPduzUQfxcz9kiLzD0yrChPU8k4%3D
 		// where img_id_token is the sha-1/base64 encoding, encoded as query parameter, of userUuid
+		if(portraitId == 0)
+			return null;
+
 		MessageDigest md = MessageDigest.getInstance("SHA-1");
 		String imageId =  URLEncoder.encode(Base64.encodeBase64String(md.digest(userUuid.getBytes())), "UTF-8");
-		
-		return "/image/user_male_portrait?img_id=" + portraitId + "&img_id_token=" + imageId;
-		
-		
+
+		return schema + "://" + host + ":" + port + "/image/user_male_portrait?img_id=" + portraitId + "&img_id_token=" + imageId;
+
 	}
 
 	/**