Fermat-type configurations of lines in P3 and the containment problem

The purpose of this note is to show a new series of examples of homogeneous ideals I in K[x,y,z,w] for which the containment I(3)⊂I2 fails. These ideals are supported on certain arrangements of lines in P3, which resemble Fermat configurations of points in P2, see [14]. All examples exhibiting the failure of the containment I(3)⊆I2 constructed so far have been supported on points or cones over configurations of points. Apart from providing new counterexamples, these ideals seem quite interesting on their own.