Dear all, We are happy to announce that the Math Forum in MathDB is re-opened. On 21 June, the MathDB server was hacked and temporarily shut down. After one week of investigation and repair, the mainpage was restored. However, the Math Forum was disabled for three months until we have setup a new server and to get it working again. We owe a special thanks to the Mathematics Department of Hong Kong University of Science and Technology for their technical support. Thank you for your support to Math Forum. Yours sincerely,