  We present redshifts for 115 emission line objects in the Hubble Ultra Deep
Field (HUDF) identified through the GRism ACS Program for Extragalactic Science
(GRAPES) project using the slitless grism spectroscopy mode of the ACS Camera
on the Hubble Space Telescope (HST). The sample was selected by an emission
line search on all extracted 1-dimensional GRAPES spectra. We identify the
emission lines using line wavelength ratios where multiple lines are detected
in the grism wavelength range (5800A < lambda < 9600A), and using photometric
redshift information where multiple lines are unavailable. We then derive
redshifts using the identified lines. Our redshifts are accurate to delta(z) =
0.009, based on both statistical uncertainty estimates and comparison with
published ground-based spectra. Over 40% of our sample is fainter than typical
magnitude limits for ground-based spectroscopy (with i_{AB}>25 mag). Such
emission lines would likely remain undiscovered without our deep survey. The
emission line objects fall into 3 categories: 1) Most are low to moderate
redshift galaxies (0 < z < 2), including many actively star forming galaxies
with strong HII regions; 2) 9 are high redshift (4 < z < 7) Lyman-alpha
emitters; and 3) at least 3 are candidate AGNs.
