1. Introduction

2. Observations and data reduction

3. Inventory of species

4. Analysis of absorption line profiles
4.1. Velocity components
4.2. The absorption along the SW line-of-sight
4.3. The absorption along the NE line-of-sight
4.4. Relative abundances
4.5. Time variations of the line profiles

5. Discussion
5.1. On the wide velocity spread of the absorption profiles
5.2. Water as a tracer of molecular gas in absorption

6. Summary and conclusions