  The BL Lac object S5 0716+71 was target of a coordinated and global
multi-frequency campaign to search for rapid and correlated variability and
signatures of the inverse-Compton catastrophe. Here we present first results
obtained from a combined analysis of the cm- to sub-mm observations over a
period of seven days aiming at a detailed study of the intra- to inter-day
variability characteristics and to obtain constraints on the variability
brightness temperatures and Doppler factors comparing the radio data with the
high energy emission recorded by INTEGRAL. A more detailed description of the
whole cm- to sub-mm observations and our analysis/results will be presented in
a forthcoming paper. Our analysis reveals the source to be in a particular
short-term variability phase when compared to the past with a correlated >~4
day time scale amplitude increase of up to 35%, which is systematically more
pronounced towards higher frequencies. The obtained frequency dependent
variability amplitudes and time lags contradict expectations from interstellar
scintillation and strongly suggest a source intrinsic origin of this inter-day
variability. A 7-day spectral evolution study indicate time-variable
synchrotron self-absorption and expansion of the emission region, consistent
with standard models. Assuming relativistic boosting, our different estimates
of the Doppler factor yield robust lower limits of D_var,IC > 5-22 using the
inverse-Compton limit and D_var,eq > 8-33 using the equipartition argument.
Although high, these values are in good agreement with Doppler factors obtained
from recent VLBI studies and from the inverse-Compton Doppler factors D_IC >
14-16 derived with the X-ray emission seen by INTEGRAL at 3-200 keV.
