Plans for BMW winner Jameka are in limbo, with the star mare found to be suffering from travel sickness on her return from Sydney to Melbourne.

Jameka was a runaway winner of Saturday's Gr. 1 BMW over 2400 metres at Rosehill, with a clash with Winx in the Queen Elizabeth Stakes on April 8 or a trip to Hong Kong for the QE II Cup on April 30 her mooted options.

Trainer Ciaron Maher told Racing NSW stewards the illness was detected when she returned to her Caulfield stable yesterday morning.

Maher said she had been treated for the illness and there was no firm decision on her next start.

Jameka, who cemented her standing as the country's best 2400-metre horse when she added the BMW to her Caulfield Cup win, will need a veterinary clearance before she races again.