We investigate the dynamics and interactions of bright solitary waves
in an optical fiber with fourth order dispersion. It is shown that rad
iationless oscillatory tails of a single soliton create a potential ba
rrier between neighbouring solitons and prevent them from interacting
strongly. The case of strong interaction, where solitons exchange thei
r energies is also considered. It is also shown that solitons with osc
illating tails exist in communication lines with lumped amplifiers and
lumped fourth-order dispersive elements.