We are glad to announce that the number 4405^2638+2638^4405 is prime (a number taken from Paul Leyland's tables, see http://www.leyland.vispa.com/numth/primes/xyyx.htm). It has 15071 decimal digits and was proven prime using fastECPP. It was a cooperation between two implementations, the one in Bonn (FKW) and the one in Palaiseau (M) by exchanging running certificates according to the available computing time. The total CPU time for FKW (resp. M) was around 520 days (resp. 200 days) on a Xeon 2.6 GHz. Large pairs (D, h) were needed, such as: 294699719 24444 2261873887 20544 4744754740 15360 8581560955 12160 The certificate is available at: http://www.math.uni-bonn.de/people/franke/x4405y2638.certif.gz J. Franke, T. Kleinjung, F. Morain, T. Wirth.