diff --git a/btm/src/main/java/bitronix/tm/resource/jdbc/JdbcPooledConnection.java b/btm/src/main/java/bitronix/tm/resource/jdbc/JdbcPooledConnection.java
index 2de404fd..c83a73dd 100644
--- a/btm/src/main/java/bitronix/tm/resource/jdbc/JdbcPooledConnection.java
+++ b/btm/src/main/java/bitronix/tm/resource/jdbc/JdbcPooledConnection.java
@@ -131,9 +131,11 @@ private synchronized void detectJdbcVersion(Connection connection) {
             }
         } catch (Exception ex) {
             jdbcVersionDetected = 3;
+            log.debug("Detected jdbc3 due to exception",ex);
         } catch (AbstractMethodError er) {
             // this happens if the driver implements JDBC 3 but runs on JDK 1.6+ (which embeds the JDBC 4 interfaces)
             jdbcVersionDetected = 3;
+            log.debug("Detected jdbc3 due to AbstractMethodError",er);
         }
         if (log.isDebugEnabled()) log.debug("detected JDBC connection class '" + connection.getClass() + "' is version " + jdbcVersionDetected + " type");
     }