What is the effect of detention of a cooperating witness in proximity to other defendants?

It is well settled that the Sixth Amendment right to counsel is violated when a private individual, acting as a government agent, "deliberately elicit[s]" incriminating statements from an accused in the absence of his counsel. Massiah v. United States, 377 U.S. 201, 206, 84 S.Ct. 1199, 1203, 12 L.Ed.2d 246 (1964). With respect to the detention of a cooperating witness in proximity to other defendants, the Massiah rule applies only to situations that " 'look' like government interrogations," United States v. Stevens, 83 F.3d 60, 64 (2d Cir.), cert. denied, --- U.S. ----, 117 S.Ct. 255, 136 L.Ed.2d 181 (1996); we have declined to "treat every inmate who hopes to cut some future deal as a 'government informant,' " id.