Use REGEX_TICKET_MENTION instead of hardcoded regular expression
diff --git a/src/main/java/com/gitblit/models/TicketModel.java b/src/main/java/com/gitblit/models/TicketModel.java
index d534589..924400f 100644
--- a/src/main/java/com/gitblit/models/TicketModel.java
+++ b/src/main/java/com/gitblit/models/TicketModel.java
@@ -43,6 +43,8 @@
 
 import org.eclipse.jgit.util.RelativeDateFormatter;
 
+import com.gitblit.Constants;
+
 /**
  * The Gitblit Ticket model, its component classes, and enums.
  *
@@ -773,7 +775,7 @@
 			}
 			
 			try {
-				Pattern mentions = Pattern.compile("\\s@([A-Za-z0-9-_]+)");
+				Pattern mentions = Pattern.compile(Constants.REGEX_TICKET_MENTION);
 				Matcher m = mentions.matcher(text);
 				while (m.find()) {
 					String username = m.group(1);
diff --git a/src/main/java/com/gitblit/tickets/TicketNotifier.java b/src/main/java/com/gitblit/tickets/TicketNotifier.java
index 8c7fe6d..1d7e4f2 100644
--- a/src/main/java/com/gitblit/tickets/TicketNotifier.java
+++ b/src/main/java/com/gitblit/tickets/TicketNotifier.java
@@ -573,7 +573,7 @@
 		// cc users mentioned in last comment
 		Change lastChange = ticket.changes.get(ticket.changes.size() - 1);
 		if (lastChange.hasComment()) {
-			Pattern p = Pattern.compile("\\s@([A-Za-z0-9-_]+)");
+			Pattern p = Pattern.compile(Constants.REGEX_TICKET_MENTION);
 			Matcher m = p.matcher(lastChange.comment.text);
 			while (m.find()) {
 				String username = m.group();
diff --git a/src/main/java/com/gitblit/utils/MarkdownUtils.java b/src/main/java/com/gitblit/utils/MarkdownUtils.java
index e0c9dd4..794d54a 100644
--- a/src/main/java/com/gitblit/utils/MarkdownUtils.java
+++ b/src/main/java/com/gitblit/utils/MarkdownUtils.java
@@ -30,6 +30,7 @@
 import org.pegdown.PegDownProcessor;

 import org.pegdown.ast.RootNode;

 

+import com.gitblit.Constants;

 import com.gitblit.IStoredSettings;

 import com.gitblit.Keys;

 import com.gitblit.wicket.MarkupProcessor.WorkaroundHtmlSerializer;

@@ -138,7 +139,7 @@
 

 		// emphasize and link mentions

 		String mentionReplacement = String.format(" **[@$1](%1s/user/$1)**", canonicalUrl);

-		text = text.replaceAll("\\s@([A-Za-z0-9-_]+)", mentionReplacement);

+		text = text.replaceAll(Constants.REGEX_TICKET_MENTION, mentionReplacement);

 

 		// link ticket refs
 		String ticketReplacement = MessageFormat.format("$1[#$2]({0}/tickets?r={1}&h=$2)$3", canonicalUrl, repositoryName);