Pastes comprise (1) siloxane copolymers which contain at least two groups of the general formula —C(O)NR1— in covalently bonded form on average per molecule, where R1 is a hydrogen atom or an alkyl radical having 1 to 18 carbon atoms and (2) organic compound(s) with a melting point greater than 0° C. which are dispersed in the siloxane copolymers (1) and contain at least one group which participates in the formation of hydrogen bridges with the —C(O)NR1 groups in (1). The pastes are useful for numerous purposes, for example as hydrophobicizing compositions.