The character 乾 (as a traditional character, read qián or gān) is such an example: it is simplified as 干 for all meanings read gān but remains to be used in its traditional shape 乾 (i.e., s=t) for all meanings read qián, in order to differentiate the two readings.
Samples for use of 乾 in simplified context as a standalone character and in compounds:
乾 qián the first of the Eight Diagrams; sky; family name
乾坤 qiánkūn heaven and earth
扭转乾坤 male and female
乾隆 Qiánlóng title of the fourth emperor's reign in Qing Dynasty, 1736—1795
乾明 Qiánmíng Buddhist temple's name
乾造 qiánzào (fortune-telling) a man's horoscope
Morpheus-Eastern, however, treats 乾 as a traditional-only form, thus also displaying dictionary entries of 乾 that are read gān and should be shown as 干 in simplified context (as in the samples above).
This is a minor problem only and but should be dealt with when we design the t2s conversion routine. There are only about a dozen of characters where the traditional shape has been split into two simplified shapes.