LimeSDR mini - Enable External Clock

I have a LimeSDR mini, version 1.2. I am using osmo-trx-lms as the transceiver. Osmo-trx-lms starts when the internal clock is enabled. However, the internal clock is not precise enough. I have an external 52 Mhz clock which I have connected. The startup of osmo-trx-lms fails when the external clock is enabled fails with "command not supported". I am using the stock, release version of osmo-trx-lms, and the command that fails is: LMS_SetClockFreq(m_lms_dev, LMS_CLOCK_EXTREF, 52000000.0). So, I just need to pass to LimeSDR that I am using an external clock with 52 Mhz.