Inclusion Criteria:

• Idiopathic Restless Leg Syndrome
• Subject has responded previously, according to medical history information, to L-Dopa therapy and/or treatment with a dopamine agonist, if pre-treated

Exclusion Criteria:

• Secondary restless legs syndrome due to, e.g., renal insufficiency (uremia), iron deficiency anemia, rheumatoid arthritis.
• Secondary restless legs syndrome associated with previous or concomitant therapy with dopamine D2 receptor antagonists, butyrophenones, metoclopramid, atypical antipsychotics (e.g., olanzapine), tri- and tetracyclic antide-pressants, mianserine, lithium or H2-blockers (e.g., cimetidine), or due to withdrawal from drugs such as anticonvulsants, benzodiazepines, barbitur-ates, and other hypnotics.
• History of sleep disturbances like sleep apnea syndrome, narcolepsy, myoclonus epilepsy observed during polysomnography (PSG) or explored in subject history.
• Clinically relevant cardiac dysfunction and/or arrhythmias (e.g., suspected conduction system dysregulations, second or third degree AV block, complete left or right bundle branch block, sick-sinus-syndrome, congestive heart failure Class III or IV by NYHA, myocardial infarction within twelve months prior to enrollment).
• Clinically relevant renal dysfunction (serum creatinine >2.0 mg/dl)
• Clinically relevant hepatic dysfunction (total bilirubin >2.0 mg/dl or ALT and/or AST greater than two times the upper limit of the reference range).
• QTc-interval in resting ECG > 450 msec in males and > 470 msec in females.
• History of symptomatic orthostatic hypotension within 28 days prior to screening visit (Visit 1), or a systolic blood pressure (SBP) less than 105mmHg at trial entry.