Disclosed is a lamp comprising a ceramic discharge vessel (3) with end parts (34) and with electrodes (4) which are connected to a respective external contact via a respective feedthrough (20). Each feedthrough is sealed with a sealing part (40) thereof by a sealing compound (10) in the end part. The discharge vessel gastightly encloses a discharge space into which said two electrodes extend from the end part and which contains an ionizable filling. The sealing compound comprises at least one first component chosen from the group consisting of ruthenium (Ru), iridium (Ir), osmium (Os) and rhenium (Re), and comprises at least one second component chosen from the group consisting of silicium (Si), boron (B), phosphor (P). Thus, a halide resistant lamp vessel is obtained exhibiting excellent lifetime characteristics and long lifetimes.