Pavel, hello! Text:
{{#multimaps:55.51999,38.089118~УИK 2628;55.489887,38.17434~УИK 2629;55.474682,38.190107~УИK 2630;55.567091,38.225898~ТИK |width=900px|height=600px}}
raises MWException (checked on my test auxiliary server and on wiki.openstreetmap.org).