Changes 
http://wiki.axiom-developer.org/290AxiomFailedToIntegrateElementaryFunction/diff
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If I try:
\begin{axiom}
integrate(simplify(((x^4*log(2*x)^2+(3*x^2-2*x)*exp(x)*log(2*x)+exp(2*x)-x*exp(x))/(x^4*log(2*x)^2+2*x^2*exp(x)*log(2*x)+exp(2*x))-1)*exp(2)),
 x)
\end{axiom}
I see that Axiom failed to recognize that e^4 - (e^2)^2 is
zero. AFAICS similar problem appears in original example:
when I trace rischNormalize I see that both e^2 and e^4
appear in "normalized" function. But this may cause
trouble later, since Axiom assumes that different kernels
are algebraically independent. 
I do not know if rischNormalize is supposed to simplify
constants (maybe this shoud be done by a separtate pass)
but failing to recognize "transcendental" zero may give
wrong results and otherwise Risch algorithm may declare
an integrable function as non integrable.

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