-- Database schema
| Web_client_accelerator : id [ INT ] primary_key , name [ TEXT ] , Operating_system [ TEXT ] , Client [ TEXT ] , Connection [ TEXT ] | browser : id [ INT ] primary_key , name [ TEXT ] , market_share [ INT ] | accelerator_compatible_browser : accelerator_id [ INT ] primary_key accelerator_compatible_browser.accelerator_id = Web_client_accelerator.id , browser_id [ INT ] accelerator_compatible_browser.browser_id = browser.id , compatible_since_year [ INT ] |
-- -- When did the web accelerator 'CACHEbox' and browser 'Internet Explorer' become compatible?

SELECT T1.compatible_since_year FROM accelerator_compatible_browser AS T1 JOIN browser AS T2 ON T1.browser_id  =  T2.id JOIN web_client_accelerator AS T3 ON T1.accelerator_id  =  T3.id WHERE T3.name  =  'CACHEbox' AND T2.name  =  'Internet Explorer';