  We consider the fractional Ornstein-Uhlenbeck process with an unknown drift
parameter and known Hurst parameter $H$. We propose a new method to test the
hypothesis of the sign of the parameter and prove the consistency of the test.
Contrary to the previous works, our approach is applicable for all $H\in(0,1)$.
We also study the estimators for drift parameter for continuous and discrete
observations and prove their strong consistency for all $H\in(0,1)$.
