diff --git a/web/src/main/java/org/springframework/security/web/util/matcher/IpAddressMatcher.java b/web/src/main/java/org/springframework/security/web/util/matcher/IpAddressMatcher.java
index a0e9409e63..3be7851094 100644
--- a/web/src/main/java/org/springframework/security/web/util/matcher/IpAddressMatcher.java
+++ b/web/src/main/java/org/springframework/security/web/util/matcher/IpAddressMatcher.java
@@ -93,7 +93,7 @@ public final class IpAddressMatcher implements RequestMatcher {
 			return InetAddress.getByName(address);
 		}
 		catch (UnknownHostException ex) {
-			throw new IllegalArgumentException("Failed to parse address" + address, ex);
+			throw new IllegalArgumentException("Failed to parse address '" + address + "'", ex);
 		}
 	}