The high/water mark values are frequently ignored and an unexpected number of threads manages to connect.
Also, an awaitAcceptable could hang forever.

For example, setting a HIGH_WATER_MARK of 10, and a LOW_WATER_MARK of 5 on a channel that has CONN_FULL status and 3 connections results in no change in the status, while the correct would be CONN_FULL status be changed to normal.

Another example is that accept enforces the total of connections to be larger than high water mark. This is inconsistent with the rest of the code, and the correct would be enforcing the total of connections to be larger or equal to the high water mark.