Address.  Antonella Cabras, Dipartamento di Matematica
Applicata ``G. Sansone",
                
Via S. Marta 3, 50139 Firenze, Italy
                
I. Kolar, Department of Algebra and Geometry, Faculty of Science, Masaryk
University,
                
Janackovo nam. 2a, 662 95 Brno, Czech Republic
 
E-mail:  cabras@dma.unifi.it
             
kolar@math.muni.cz
 
Abstract.  First we deduce  some general properties 
of product preserving
bundle functors  on the category of fibered manifolds. Then we
study the prolongation of projectable tangent valued forms with
respect to these functors and describe the complete lift of the
Fr\"olicher-Nijenhuis bracket. We also present  the coordinate
formula  for composition of semiholonomic jets.
 
 
AMSclassification. 53C05, 58A20.
Keywords. Projectable tangent valued form, product preserving bundle functor, jet, Weil bundle, Fr\"olicher-Nijenhuis bracket.